I'm so slow and far behind with JS tool, but, at least, came up to something [not so usable] what could be tested. It's in 
js-tool branch and could be ran with
	Code:
	python27 tool/js/js_resources.py extract -m pillow -s /path/to/whole/pillow/directory -d /path/to/dest/dir/for/extracted/properties
 or with
	Code:
	python27 tool/js/js_resources.py extract -m waf -s /path/to/whole/waf/directory -d /path/to/dest/dir/for/extracted/properties
 Whole Pillow directory is the 
/usr/share/webkit-1.0/pillow from KT. And 
whole WAF directory is the 
/var/local/waf from KT.
It will create .properties files with extracted resources within directory structure from 
this post. (if 
src/5.0.0/{pillow, waf} will be given as 
-d value)
Extract mode isn't complete yet (it lacks of writing of metadata). And compile mode isn't implemented at all (it requires metadata). Metadata will contain name of top-level variable, name of constructor (for that string from media bar resources), etc. Extracting of metadata from JS is aready implemented.
So, 
ixtab, could you check list of JS files to process (they are listed at 
tool/js/pillow.manifest and 
tool/js/waf.manifest) and, maybe, try to test the tool?
And, of course, congratulations for the update bundles creation! Thanks!